In previous work we have found tht in sperm flagella the contractile fibers are activated over the entire length at once. This leads to a simple model for the coordination of the contractile events in flagella. An equation has been derived which formulates this model and which should be applicable to cilia and flagella. Preliminary results show that ciliary motion can indeed be described by the model. It is proposed to work out the model for various types of ciliary and flagellar motion. The role of the basal body in the control mechanism of cellular flagella will be investigated. The technique to be employed consists of specific destruction of the basal body by laser micro irradiation, followed by attempts to reactivate the flagellum. The nature of the carrier molecule for the control signals from cells to cellular flagella will be investigated by means of micro injection of specific inhibitors.